HarmonyOS鸿蒙Next中如何在子线程中获取Context

在worker线程中不支持直接使用getContext接口获取主线程的context信息。主线程和worker线程的上下文不一致。需要子线程中获取Context时，需要将主线程的context通过消息的方式传输到worker线程中。

主要业务代码：主线程：

import { ErrorEvent, MessageEvents, worker } from '@kit.ArkTS';
const workerInstance = new worker.ThreadWorker("entry/ets/pages/workers/worker1.ets");
@Entry
@Component
struct Index {
  @State message: string = 'Hello World';
  build() {
    Row() {
      Column() {
        Text(this.message)
          .fontSize(50)
          .fontWeight(FontWeight.Bold)
        Button("向worker发送消息").onClick(() =>{
          let con: Context= getContext()
          workerInstance.postMessage(con);
        })
      }.width('100%')
    }.height('100%')
  }
}

worker线程：

import worker, { MessageEvents, ErrorEvent } from '@ohos.worker';
import { Context } from '@ohos.abilityAccessCtrl';
// 创建worker线程中与主线程通信的对象
const workerPort = worker.workerPort
// worker线程接收主线程信息
workerPort.onmessage = (e: MessageEvents): void => {
  let con: Context = e.data;
  console.error("ctest show worker监听到消息worker.ets onmessage"+con.filesDir)
}
// worker线程发生error的回调
workerPort.onerror = (err: ErrorEvent) => {
  console.log("worker.ets onerror"+ err.message);
}